عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Topographic conditions of the ground surface are intensively effective on the climatic moderate phenomena. Etangs are considered more or less the focal point of accumulation of cold air during the night and may cause the appearance of air temperature collapse. Normal of the air temperature in synoptic and climatological stations shows such conditions for Gavkhoni etang. In this research, Markov Chain model was used for determining the probability of occurrence of days with settlement of cold air in Gavkhoni etang in different seasons of the year.
Therefore, the minimum difference of daily air temperature at the two climatic stations of Varzaneh and Isfahan in statistical period (2005-1986), was obtained And with respect to its sign ( negative or positive) , the days of the year were divided in two categories of ordinary days with code (zero) and the days with accumulation of cold air in etang with code (1).
The results showed that %71.5 of the days of the year had the settlement of cold air in Gavkhooni etang.
The number of the days with accumulation of cold air in the autumn, winter , spring , and Summer were %79.5, %73.8, %71.9 and %61.1respectively. In cases of conditional transition of temperature, the probability of p11occurance is more than other conditions ( ، ، ). Regression relation between the observed and estimated values of n periods of cold air settlement shows that the considered accuracy and reliability for all seasons is more than 99%.